Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.

Diagnosis help needed --controller?

I have an 8-location WeatherMatic
Mark *A controller on a sprinkler system
which uses 7 of the 8 dtations (several
sprinklers on ach)
Recentlty, I had an old valve fail
and replaced it ( I've done this sucessfully
on two or three other occassions --it's
an old system and I seem to have a vaalve fail each year!)
When I restarted the system none of the three
valves in the valve box ehere I replaced one will
work. I have water at all three, manually the valves
work, and I have 24V A.C. currecnt getting
to the valves. All other locations work normally.
I don't understand how the valves work ---I had
presumed that the power we turned on to open a valve
but apparently not---these three have power.
I did nothing to the other two valves in this box
and all worked fine before this one failed (a crack
in the plastic base).
I'm bewildered --any help appreciated ---
e-mail please as I won't be here daily.
Thanks

Check your wiring for continuity, especially the common. As for valves having power, never assume. People check for voltage, and assume they're good to go, but that isn't always the case. Checking wiring resistance is better. (beyond that, you can check for operating current, but that's getting advanced)

Check wring resistance between what and what? Through the valve magnet?
I have checked the wiring at the valves. I find it hard to believe that 3
valves failed at once --including one that has never been used --just installed
Continuity where?
How do these valves work if they have power all the time --what causes them to open?
That is what does the controller do to open the valves since they already have power??

Obtain a multimeter. Even a cheapie Radio Shack VOM will do. Measure the resistance of your valve wiring, including the solenoids. The odds are good that you find no continuity in the circuit. That points at your own work, or a broken common wire somewhere else.

Hi Jack. The valves do not have power "all" of the time. There should only be power to the valve when the timer send a signal. If all three valves have power at the same time then this might be your problem. Only one valve at a time has power but only when it's time to water. Check your wiring.